Bicycle frame



FIG. 1 is a side elevational view of a bicycle frame embodying our new design;

FIG. 2 is a top plan view thereof;

FIG. 3 is a bottom plan view thereof;

FIG. 4 is a front elevational view thereof;

FIG. 5 is a rear elevational view thereof, the side not shown being a mirror image of side shown; and,

FIG. 6 is a perspective view from the top, front and one side thereof. 

The ornamental design for a bicycle frame, as shown and described. 